Continuing CA final after getting ATC degree

As per -

https://www.icai.org/post.html?post_id=3748&c_id=121

(b) Candidates who have passed the Professional Education (Examination II) in entirety under the Chartered Accountants Regulations, 1988 and had also completed the prescribed period of articled training including excess leave, if applicable.

So, your friend is required to do the computer training (if not done already), complete articleship (if not done already), in order to obtain the Accounting Technician certificate, which can be applied for, here -

https://icai.org/post.html?post_id=3765&c_id=285

More details -

https://www.icai.org/resource_file/14288atc-ipcc_111208.pdf

In order to appear for final, he can do so in last 6 months of articleship, if not already completed, if completed, he can sit in the next exam.